...Just checked the CamcorderInfo review for HBlack's Elura 90 camera. You can see that it has a yellow AV output which can also be used directly with headphones. So he can simply plug a set of headphones directly into the camera to monitor his audio.
CamcorderInfo Review of the Canon Elura 90
http://www.camcorderinfo.com/content/Canon-Elura-90-Camcorder-Review.htm
CamcorderInfo Review of the Canon Elura 90
http://www.camcorderinfo.com/content/Canon-Elura-90-Camcorder-Review.htm